A term originating from the phone sex industry. It is common to find it scribbledon the wall of a public restroom along with the number of somebody the person wanted to annoy/bother.

"So I found this number on the bathroom stall and it said "call for a good time" above it. But instead of a sex hotline it was just some dude's ex. My dissapointment is imeasurable, and my day is ruined.